INTRODUCTION TO SPACESCIENCES AND SPACECRAFT APPLICATIONS INTRODUCTION TO SPACESCIENCES AND SPACECRAFT APPLICATIONS BRUCEA. CAMPBELL AND SAMUEL WALTER MCCANDLESS,JR. Gulf Publishing Company Houston, Texas Introduction to Space Sciences and Spacecraft Applications Copyright 0 1996 by Gulf Publishing Company, Houston, Texas. All rights reserved. Printed in the United States of America. This book, or parts thereof, may not be reproduced in any form without permission of the publisher. Gulf Publishing Company Book Division P.O. Box 2608 Houston, Texas 77252-2608 10 9 8 7 6 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Campbell, Bruce A., 1955- Introduction to space sciences and spacecraft applications / Bruce A. Campbell, Samuel Walter McCandless, Jr. p. cm. Includes bibliographical references and index. ISBN 0-88415-411-4 1. Astronautics. 2. Space vehicles. I. McCandless, Samuel Wal- ter. 11. Title. TL791.C36 1996 629.4-dc20 96- 14936 CIP Printed on acid-free paper (=) iv Contents Acknowledgments viii About the Authors viii Preface ix CHAPTER 1 Introduction and History 1 Uses of Space, 1. History of Spaceflight, 3. ReferencedAdditional Reading, 23. Exercises, 23. PART 1 SPACE SCIENCES CHAPTER 2 Orbital Principles 26 Orbital Principles, 28. Orbital Elements, 38. Orbital Properties, 39. Useful Orbits, 44. Orbit Establishment and Orbital Maneuvers, 47. ReferencedAdditional Reading, 5 1. Exercises, 5 1. CHAPTER 3 Propulsion 53 First Principles, 54. Orbit Establishment and Orbital Maneuvers, 63. ReferencedAdditional Reading, 74. Exercises, 74. CHAPTER 4 Spacecraft Environment 76 The Sun, 76. The Earth, 87. Spacecraft Effects, 97. ReferencedAdditional Reading, 101. Exercises, 101. V PART 2 SPACECRAFT APPLICATIONS CHAPTER 5 Communications 104 Communications Theory, 104. Modulation, 115. Digital Communications, 118. Communications Systems, 128. ReferencedAdditional Reading, 129. Exercises, 129. CHAPTER 6 Remote Sensing 132 Remote Sensing Principles, 135. Measurement Dimensions of Remote Sensors, 146. Remote Sensing Satellites, 149. ReferencedAdditional Reading, 150. Exercises, 151. CHAPTER 7 Satellite Navigation 154 Position Determination Using Doppler Techniques, 154. Pulse Ranging and Phase Difference Positioning, 159. ReferencedAdditional Reading, 164. Exercises, 164. PART 3 SPACECRAFT SYSTEMS AND DESIGN CHAPTER 8 Spacecraft Systems 166 Satellite Design, 166. Ground Support Systems, 192. Space System Evolution, 195. ReferencedAdditional Reading, 196. Exercises, 197. CHAPTER 9 Spacecraft Design 198 The Systems Approach, 198. Spacecraft Systems, 209. ReferencedAdditional Reading, 210. Exercises, 2 10. vi APPENDIX A Manned Spaceflight Summary 21 1 APPENDIX B United States and Foreign Spacecraft Inventories and Spacecraft Descriptions 21 7 Index 230 vii Acknowledgments The authors express appreciation to all the colleagues and students whose reviews and comments helped to shape and refine this book. About the Authors Bruce A. Campbell is currently involved in spacecraft project man- agement at NASA's Goddard Space Flight Center. He is an aerospace engineering graduate of the U.S. Naval Academy and flew carrier-based jet aircraft as a Naval Flight Officer. Samuel Walter McCandless, Jr., is president and founder of User Sys- tems, Inc., which provides airborne and space-based radar and microwave sensor and system design and evaluation, remote sensing and satellite sys- tem design, and associated services. He was test director for NASA's Sur- veyor 1 spacecraft and managed NASA's Seasat program from its incep- tion through operation of the satellite in space. viii Preface In 1985, the authors were asked to create an introductory course for a new series of classes focusing on space systems engineering in an under- graduate aerospace engineering curriculum. Although the authors were familiar with separate texts on each of the subjects to be taught, there seemed to be no single existing text that covered all the topics at a level that could be used for an introductory class. The first time the course was taught, handouts were created for each of the topics covered. Each suc- cessive time that the course was taught, the handouts were updated based on the experience of the preceding class. The idea to publish came very early, and the handouts evolved into the chapters that make up this text. In its manuscript form, this text has been used by several hundred stu- dents, in several different institutions, under different instructors, with very favorable reviews. The most common comment is the ease with which the student can read and understand the material. Although the text is geared toward sophomore/junior undergraduate engineering students who will continue to take courses in these space-related topics, it has proven to be comprehensible and interesting to students in other science and nonengineering fields as well. The subjects are introduced on a basic level with no prior related knowledge expected of the student. A funda- mental knowledge of physics, differential equations, dynamics, and other pre-engineering subjects is helpful, but not necessary, to understanding the basic concepts presented. To emphasize this point, the subject matter of the text has been con- densed into a “short course” that has been presented to many diversified groups of managers, technicians, military personnel, and other profes- sionals-not necessarily engineers-over the past several years. Many of these people are involved in space systems acquisition or operation, and most report that the course provides them with a more complete level of understanding that makes them more comfortable in their fields and which they believe will help them in their professions. The text material has proven to be an excellent reference and review source for the student and professional alike. This text considers many of the interdisciplinary topics necessary for understanding the design and application of space-based systems. The ix space science topics include orbital mechanics (Chapter 2), propulsion (Chapter 3), and a description of the space environment (Chapter 4). These chapters prepare the way for discussing spacecraft applications. The most common uses of systems in space include communications (Chapter 5), remote sensing (Chapter 6), and navigation (Chapter 7). Finally, the basic systems required by most spacecraft (Chapter 8) and a methodology used to design a spacecraft (Chapter 9) are presented. In a four-year, semester-oriented undergraduate institution, it is recom- mended that this text be used for a 3-credit-hour (2 hours classroom, 2 hours laboratory) course given at the end of the sophomore year or begin- ning of the junior year. By this time the student should be familiar with most of the helpful subjects discussed above and will be ready to take this course and, if desired, any of the follow-on space topic courses. Early in the course, the laboratory hours can be used for additional classroom hours and problem solving; however, as the course progresses, laboratory hours could include orbital mechanics computer simulations, Estes rock- et firings, an “outside” environmental lab, a communications lab, review of some remote sensing materials or films, a GPS navigation demonstra- tion, or other demonstrations that help the student get a feel for the sub- jects discussed. Later in the course, the laboratory hours should be devot- ed to the formulation of an idea for a space-based application and the top-level conceptual design of a system to fit the need. This text could also be used for a 2- or 3-hour classroom-only course which might be more suitable to the nonengineering student or two-year institution. X CHAPTER 1 Introduction and History To set the stage for what is presented in this text, a brief discussion on the uses of systems in space is provided as insight into the operation and purposes of such systems. This discussion is followed by a brief history of man’s achievements in space and some conjecture on where we may be headed. USES OF SPACE For centuries, the stars and planets and their patterns and positions have been used for purposes similar to those for which we use modem space sys- tems. Notable and ancient applications include navigation and environmen- tal prediction. So it is surprising that even after Sir Isaac Newton showed that man could, theoretically, place an object into space, no one immediate- ly thought of any useful reason why anybody would want to. It was not until this feat was actually accomplished that we began to explore and discover the benefits offered by presence in space and began designing and building systems to take advantage of this wonderful new dimension. After the first few pictures were returned from some of the early sub- orbital test rocket flights, experimenters recognized that one of the great- est advantages of being in space was the expanded perspective looking back toward earth. The ability to view areas of the globe large enough to show entire storm patterns spawned the science of global environmental remote sensing. This has dramatically increased knowledge of the envi- ronment, allowing for the observance and prediction of adverse condi- tions and thereby saving life and property from disaster. Remote sensing systems also allow us to discover and monitor natural resources and eval- uate demographic effects such as urban expansion and pollution. Similar type sensors, positioned outside the blanket of the earth’s atmosphere and 1 2 Introduction to Space Sciences and Spacecraft Applications on